Aida was written for the two-year-old Cairo Opera House. The Khedive (Ismail Pasha, the Viceroy of Egypt for the Ottoman Empire and a fan of all things European) was determined to commission a magnificent opera to open the new opera house in Cairo.
Verdi had previously rejected the offer to write an inaugural hymn for the opening of the Suez Canal in 1869 (the same year the opera house opened with Verdi's Rigoletto).
Camille du Locle persuaded Verdi to take on the Aida project with a little Psych 101. He told him that if Verdi didn't want the job, Richard Wagner might be interested and would probably do a very good job with it!
He also wrote in a letter to Verdi that the Khedive would be willing to give him almost anything: "If you were to ask for a pyramid (the biggest one, of course) as a bonus, he's just he sort of person who might give it to you."
The writer of the original scenario of Aida, Auguste Mariette was an archaeologist and Egyptologist who worked for the Khedive. Having had a little experience in his youth in drawing and design, he was hired to design the sets and costumes for the premiere production.
The so-called Aida trumpet was specially constructed for the premiere of the opera. Used in the Triumphal March in Act II, it was based on the trompette thébaine (trumpet of Thebes) which only produced four notes and was originally copied from the images in ancient Egyptian reliefs. It was Verdi's belief that on-stage ancient Egyptians could not be seen playing modern, valved instruments.
For most of his operas Verdi worked with his publisher Ricordi to produce not just an opera score, but also a production book which acted as the official guideline for directors. These books are full of detail as to how the operas should be staged. The Aida book is one of the most detailed, with instructions on how performers should look and move, with instructions that any tenor playing Radames should be clean shaven!
Aida is a product of Verdi's late career. It's an intimate piece of theatre within the greater context of grand opera. There are some reminders of his earlier style and it was for this reason that some critics were not so impressed with Aida when it premiered. But this opera also possesses a melodic and dramatic psychological expression that showed a new step in his artistic growth, one which foreshadowed his remarkable Otello. Verdi himself described Aida as one of his "modern operas . . . made with ideas, not made up of cavatinas, duets, etc."